Suction pipe for an internal combustion engine with a spray carburetor

ABSTRACT

A suction pipe for an internal combustion engine with a spray carburetor having two parallel mixing chambers each of which has a conduit for the mixture. The suction pipe is particularly characterized by a channel joining the mixing chamber of the first stage and extending below a widened conduit connected to the second stage. The channel is provided with inserts which produce eddies and its projection upon an imaginary horizontal plane is perpendicular to the projection of the widened portions of the conduit.

U United States Patent 1 1 3,607,155

[72] Inventor Georg Faltermeier [56] References Cited Wolnmh, GermanyUNITED STATES PATENTS [21] P 878399 9 2,072,353 3/1937 Ball 123/141 [22]196 2,684,059 7/1954 Schneider..... 48/180 x Pmmed 1971 2 966 150l2/l960 Wiltshire et al 123/141 [73] Assignee Audi NSU Auto UnionAktlengesellschalt Danube, Germany Primary Examiner-Morris O. Wolk [32]Priority Dec. 10, 1970 Assistant Examiner-R. E. Serwin [33] GermanyAttorney-Richards & Geier [31] P18141292 [54] SUCTION PIPE FOR ANINTERNAL COMBUSTION ABSTRACT: A suction pipe for an internal combustionen- ENGINE WITHA SPRAY CARBURETOR h b h t u l h 5 Chin, 2 Drawing Figs.gme w1t a spray car uretor ai mg wo para e m1x1ng c ambers each of wh1chhas a conclult for the mlxture. The suct1on [52] U.S. Cl. 48/180 R, pipeis particularly characterized by a channel joining the mix- /1 123/141ing chamber of the first stage and extending below a widened [51] lnt.Cl801i 3/02, conduit connected to the second stage. The channel is pro-F02m 17/00 vided with inserts which produce eddies and its projection[50] Field of Search 48/180 R, upon an imaginary horizontal plane isperpendicular to the projection of the widened portions of the conduit.

Fig.1

Inventor: G. Falter-maelmwwgw ATTOIL N615 PATENIED sEm IHYI 7 3.607155sum 2 OF 2 lnyentor: G. Fali arm 6661* A TTOFLNEBS SUCTION PIPE FOR ANINTERNAL COMBUSTION ENGINE WITH A SPRAY CARBURETOR This inventionrelates to a suction pipe for an internal combustion engine with a spraycarburetor having two parallel mixing chambers with separate conduitsfor the mixture.

A machine provided with such a carburetor can have a substantiallyuniformly composed mixture of fuel and air over its entire range ofrevolutions, since the speeds of flow of air through the two mixingchambers are greater than when only one mixing chamber is used.Nevertheless, when the machine is operated with the first mixingchamber, fuel is deposited in the suction pipe. To provide a good outputfor the machine the carburetor must be set at that stage to a fattermixture. This results in a high fuel consumption, and also in an exhaustgas having a high amount of poisonous components.

An object of the present invention is to eliminate or diminish by simplemeans these drawbacks of prior constructions.

Other objects of the present invention will become apparent in thecourse of the following specification.

In the accomplishment of the objectives of the present invention it wasfound desirable to provide a channel joining the mixing chamber of thefirst stage and extending under a widened conduit which joins the secondstage. The channel is provided with inserts which produce stage. Thechannel is provided with inserts which produce eddies. The projection ofthe channel upon an imaginary horizontal plane is perpendicular to theprojection of the widened part of the conduit.

During operation with the first stage of the carburetor, thecomparatively thin mixture is so diluted prior to its entry into suctionpipe branches at the eddy-producing inserts that a practicallyhomogenous mixture is present at the end of the channel having theinserts. The following suction pipe branches have, therefore,substantially no influence upon the composition of the mixture which issupplied to the individual cylinders. An intensive heating of thesuction pipe is not necessary any more since the eddies have a moreimportant and greater effect on evaporation.

To simplify construction, the inserts producing the eddies can be castin a wall constituting a lower end for the channel and this wall can bepreferably made a part of a removable cover.

As inserts producing the eddies are preferably used V- shaped rods withthe vortex of the V being located in the direction of flow of themixture.

The invention will appear more clearly from the following detaileddescription when taken in connection with the accompanying drawings,showing, by way of example only, a preferred embodiment of the inventiveidea.

In the drawings:

FIG. 1 is a perspective section through a device of the presentinvention;

FIG. 2 is a top view of one of the parts.

FIG. 1' shows a spray carburetor 2 connected with a suction pipe 1. Themixing chambers 3 and4 of the carburetor extend parallel to each other.A channel 5 is connected to the mixing chamber 3 of the first stagewhile a conduit 6 is connected to the mixing chamber 4 of thesecond'stage. The conduit 6 is widened and extends into the individualsection pipe branches, for example, four branches. At 7 the channel 5opens into the widened part of the conduit 6. Inserts 8 which produceeddies, extend into the channel 5. A imaginary projection of the channel5 upon its lower wall 9 extends vertically to the imaginary projectionof the widened portion of the conduit 6. The wall 9 is a component partof the removable cover 10. The inserts 8 are cast upon the cover 10,they are constructed as V-shaped profiled rods with the vortex of the Vextending in the direction of flow of the mixture.

When the internal combustion engine is running, it receives a mixture ofair and fuel through the mixing chamber 3 and the corresponding openthrottle valve. The throttle valve of the mixing chamber 4 of thesecond, stage 18 then closed. The

thinned mixture flows out of the mixing chamber 3 into the channel 5 andreceives a turbulent motion from the inserts 8. Little drops which arecarried along are diminished while flowing around the inserts 8 and areevaporated when the thinned mixture enters the widened portion of theconduit 6 through the passage 7.

Consequently, a nearly homogenous mixture will flow in the widenedportion of the conduit 6. When further gas is supplied, the throttlevalve in the mixing chamber 4 will also open in the usual manner andwill supply a mixture for the middle and upper power ranges.

. Iclaim:

1. In an internal combustion engine, in combination with a suction pipe,a spray carburetor comprising two parallel mixing chambers for the firstand second stages, respectively, a channel connected to the mixingchamber of the first stage, a conduit having a widened portion andconnecting the mixing chamber of the second stage with the suction pipe,said channel extending under said widened conduit portion andcommunicating therewith, and eddies-producing inserts in said channel,the projection of said channel upon an imaginary horizontal planeextending perpendicularly to the projection of the widened portion ofsaid conduit.

2. A device in accordance with claim 1, wherein said channel has abottom wall carrying said inserts.

3. A device in accordance with claim 2, wherein said inserts are castupon said bottom wall.

4. A device in accordance with claim 2, comprising a removable cover,said bottom wall being a part of said cover.

5. A device in accordance with claim 1, wherein said inserts consist ofV-shaped profiled rods, the vortex of the V extending in the directionof flow of the combustion mixture.

2. A device in accordance with claim 1, wherein said channel has abottom wall carrying said inserts.
 3. A device in accordance with claim2, wherein said inserts are cast upon said bottom wall.
 4. A device inaccordance with claim 2, comprising a removable cover, said bottom wallbeing a part of said cover.
 5. A device in accordance with claim 1,wherein said inserts consist of V-shaped profiled rods, the vortex ofthe V extending in the direction of flow of the combustion mixture.